1. Field of the Invention
The present invention relates generally to spring balance systems for sliding windows. More particularly, the invention relates to an externally mounted replacement window spring balance device assembly for single or double-hung sash windows.
2. Description of the Prior Art
A typical window frame assembly includes two or more glass panes secured, respectively, in an upper window frame and a lower window frame. The lower window frame is generally moveable from a closed position upwardly to an open position adjacent to and alongside the upper window frame.
The present invention addresses a common problem of maintaining the lower window sash in the open position. This condition is encountered when one or both of the window spring balances or other counter balance devices, typically mounted internally to the window frame and laterally opposed to the lower sash edges, become inoperative. Additionally, some windows utilize friction between the lower sash edges and the window frame guide to keep the lower window sash in the open position. Over time the frictional forces may lessen due to frictional wear. The lower window sash may even suddenly fall to the closed position, making a loud noise and causing the glass to crack or shatter. There exists the possibility that injury could occur due to the falling window or the broken glass. Even with window sashes equipped with a mechanism to keep the window in the open position, if the mechanism becomes inoperative and the frictional forces of the window sash edges and the frame guide lessen over time, the potential for the window unexpectedly falling still exists.
There are several U.S. patents that disclose devices for overcoming this problem. For example, U.S. Pat. No. 494,959 issued to Kimball describes a sash balance where a case with a spring drum is attached to the window jamb, and a tape connected to the drum is extended down and attached to the sash.
U.S. Pat. No. 518,278 issued to Rosentreter discloses a sash balance that is designed to be thin so it may be adapted to car windows as well as windows of larger size. The sash balance consists of a case with a side plate, a drum fitted thereto, a rivet uniting the parts, a spring connecting the drum with a hub of the case, a tape winding on the drum, a spring disk set into a cavity of the case held by the rivet and serving to draw against the side plate.
U.S. Pat. No. 601,283 issued to Sawyer, et al. claims a sash lift comprising parallel, vertical brackets, a spring-actuated revoluble shaft mounted transversely therein, a grooved drum mounted on said shaft and revolving therewith, a sash cord adapted to wind in said drum and connected with the sash, a peripheral ratchet on said drum, a pawl adapted to engage therewith, a pivoted bell-crank lever mounted on one of the side rails of the window-casing, a cord connecting the pawl and an arm of the bell-crank lever, a pull rod provided with a knob-ended integral right-angular arm at its lower end, said rod adapted to move vertically in a stationary cylindrical casing secured to the side rail of the window casing below said pivoted bell crank lever, and a cord connecting said rod with one arm of said bell crank lever.
U.S. Pat. No. 869,512 issued to Ocumpaugh discloses a drum casing for sash balances and pulleys for placement of the type for placement on the upper window casing. The casing is for containing a coil type spring and a recoiling tape for attachment to the lower window sash.
U.S. Pat. No. 1,121,228 issued to Burkhart describes an automatic sash lock and opener. The device will automatically lock the sash when it is moved to its closed position. The device also automatically opens the sash to a pre-determined height when the locking mechanism is released. The device consists of a keeper having a downwardly facing shoulder secured to one side of the frame, a vertically disposed rod connected to the lower end of the sash, the upper end of the rod being bent to form a hook for engagement under the shoulder of the keeper when the sash is moved to the closed position, means for releasing the hooked upper end of the rod from beneath the shoulder of the keeper, and means for automatically drawing the rod upwardly after the same has been released from the keeper to open the sash a predetermined distance.
U.S. Pat. Nos. 2,637,875 and 2,659,929 issued to Hess discloses a spring assembly that can be used as a window balance. The spring balance is comprised of pre-tensioned and pre-torsioned helical spring secured at one end to a rod which is axially arranged within the spring and mounted for rotation in a bracket. The rod is provided with an abutment on its end to maintain it in assembled position. The bracket is for attachment to a movable object such as a window frame. The opposite end of the spring is attached to a guide which is a tube having a guideway at its upper end for the reception of the rod, which rod and guide are adapted to move relatively in respect of each other in axial and rotative directions. A securing member attaches the guide tube as well as the spring to a bracket which is adapted to be secured to the window sash.
U.S. Pat. No. 2,817,872 issued to Foster discloses a window sash balance comprising a housing with an enlarged portion provided with a partial circumferential surface, a tongue portion integral with the housing and flanged around its periphery and extending from the opposite end of the enlarged portion, a tongue portion integral with the housing and flanged around its periphery and extending from the opposite end of the enlarged portion, a plurality of cross ribs extending across the tongue portion and connected to the flanges around the periphery, and the housing being adapted to receive a coiled ribbon spring which rotates on the part-circumferential surface when the window is raised or lowered.
Finally, U.S. Pat. No. 5,924,683 issued to Alchin describes a spring balance system for sliding windows. The system is a self contained apparatus comprised of a small diameter tube and a larger diameter tube. The two tubes are telescopic with respect to one another. A spring extends through the length of both tubes. At one end there is a means for attaching the apparatus to a sliding window. The other end comprises a support.
It is an object of the present invention to provide an externally mounted replacement window spring balance device assembly which eliminates the need to disassemble the framework of the broken window assembly to access the internal broken or worn out balance device for replacement.
It is another object of the invention to provide an externally mounted replacement window spring balance device assembly which can support windows having internal window spring balances, counter weight devices, and windows previously utilizing track friction which has lessened due to wear.
It is another object of the invention to provide an externally mounted replacement window spring balance device assembly wherein the assembly mounts externally to the window frame assembly.
It is another object of the invention to provide an externally mounted replacement window spring balance device assembly which is versatile to use on almost any size or weight window sash through the availability of various lengths and strengths commercially available window spring balances,
It is another object of the invention to provide an externally mounted replacement window spring balance device assembly which does not require disassembly of the window frame and accompanying trim work.
It is another object of the invention to provide an externally mounted replacement window spring balance device assembly which eliminates the need to caulk and repaint the window frame and trim work after repair.
It is another object of the invention to provide an externally mounted replacement window spring balance device assembly which uses standard mechanical fasteners, such as screws, and a screwdriver for installation.
It is another object of the invention to provide an externally mounted replacement window spring balance device assembly which reduces the time required to repair a window assembly with broken or worn out balance devices.
It is another object of the invention to provide an externally mounted replacement window spring balance device assembly which allows simple and easy installation by persons with limited mechanical, handyman, or craftsmanship skills.
It is another object of the invention to provide an externally mounted replacement window spring balance device assembly which does not interfere with window dressings such as window blinds which mount on top of the window frame.
It is another object of the invention to provide an externally mounted replacement window spring balance device assembly which allows the window spring tension to be increased or decreased without disassembling the window frame.
It is another object of the invention to provide an externally mounted replacement window spring balance device assembly which resembles standard wood window trim.
It is another object of the invention to provide an externally mounted replacement window spring balance device assembly which is easily removable for standard maintenance of the window frame and/or sashes, such as for painting.
It is another object of the invention to provide an externally mounted replacement window spring balance device assembly which allows the outer cover to be interchangeable with differently decorated or shaped covers.
The foregoing and other objects of the invention are achieved by an externally mounted replacement window spring balance device assembly comprised of a housing, a spring balance, a housing cover, a top cap, a bottom cap, and a track which engages longitudinal grooves formed in the housing.